Fall Blast Of Heat Triggers Advisory, Fire Worries For The Bay Area

SAN FRANCISCO — A run of unseasonable heat has arrived in the Bay Area, with afternoon temperatures forecast to run well above normal through Saturday and little relief expected overnight.

The National Weather Service issued a heat advisory Thursday covering San Francisco, the Bay Area coastline, most of the Peninsula, the Santa Clara Valley, the Santa Cruz mountains, and expanding to include coastal areas of Monterey Bay, northern Salinas Valley and Carmel Valley.

The advisory is due to expire at 11 p.m. Friday, but forecasters warn the warmth is unlikely to let up much until late in the weekend.

"Warm temperatures expected through the end of the week with elevated Heat Risk across much of the interior," NWS Bay Area wrote Thursday morning. "Heat will begin to ease on Saturday but will still [be] 5 to 15 degrees above climatological normals. Cooler temperatures really arrive Sunday into early next week as [a] pattern change will be underway."

Portions of the Santa Clara Valley, including San Jose, are likely to hit the 90s on three consecutive days. A similar story will play out on the Peninsula, the North Bay and the East Bay. Updated forecasts showed that even San Francisco could hit 90 degrees Thursday afternoon.

Forecasters warn overnight lows will run warmer than usual, limiting relief for heat-sensitive groups, and several days of dry heat will create new fire risks across the region.

"Above normal temperatures and moderate-to-major Heat Risk will increase the potential for heat-related illnesses, particularly for those participating in outdoor activities," the heat advisory reads in part. "In addition to the heat, individuals should be mindful of the elevated fire danger into the weekend, especially inland and at higher elevations where there will be no overnight relief from the marine layer."

According to the National Weather Service, temperatures will cool considerably by Monday and there is a hint in early models that some welcome rain may be possible early next week.